Structural, magnetic and XPS studies of Sn0.95Co0.05O2-0.05 and Sn0.95Fe0.05O2-0.05 nanoparticles

Structural, microstructural, X-ray photoemission spectra (XPS) and magnetic properties of transition metal ion [5 mol% of Co (SC5) and Fe (SF5)]-doped SnO2 nanoparticles have been studied. The SC5 and SF5 nanoparticles were synthesized by a chemical route using polyvinyl alcohol as surfactant. The doped SnO2 crystallites were found to exhibit a tetragonal rutile structure and the average grains size was measured by the Scherer relation of X-ray diffraction. Transmission electron micrographs showed that the average grain size of SC5 is smaller than SF5. SC5 nanoparticles showed strong ferromagnetic behaviour but SF5 exhibited an F-centre exchange (FCE) mechanism. Temperature-dependent magnetization showed the values of phase transition temperature. XPS confirmed the presence of SnOCo and SnOFe bonds in these SC5 and SF5 nanoparticles. The oxidation states of Sn, Co and Fe were found to be +4, +2 and +2, respectively, while the core level XPS peaks of Sn 3d, O 1s, Co 2p and Fe 2p were analyzed